A discovery I made *suggests* that some spells from Wrath of the Lich King may already be in version 2.1.3.
While, sadly, it does not work as intended in private servers, there is a spell called Crypt Scarabs. "Summons 6 Crypt Scarabs to aid the caster in battle for 10 sec."
Another spell, Touch of Death, I have never seen in the game. Ever. Not from classes, not from mobs, not from anything. This suggests it is made for use in the future.
"Steals <###> to <###> life from the target".
Touch of Death.
With these spells in mind, and others burning on the back of my head, I have decided to switch from my current project (Demon race) to a Death Knight class (replacing Paladin), compatible with 2.1.x. More info on that in another post..
Note: I can not guaranty that these are from WotLK. Nor can I guaranty that Touch of Death is never used. If you think I'm wrong, fine. But please, do not flame this post, for it is of mere curiosity that I post this.